(define (make-rat n d)
    (if (< d 0)
        (make-rat (* -1 n) (* -1 d))    
        (let ((g (gcd n d)))
            (cons (/ n g) (/ d g))
        )
    )    
)
(define (print-rat x)
    (newline)
    (display (car x))
    (display "/")
    (display (cdr x))
)
(print-rat (make-rat -3 -4))
(print-rat (make-rat 3 -4))
(exit)